Benzodiazepines are a class of drugs which possess sedative and tranquilizing properties. The benzodiazepines are used clinically to treat a variety of ailments, including depression, anxiety, insomnia and muscle spasms. The class of benzodiazepines include alprazolam, bromazepam, clonazepam, diazepam, flunitrazepam, flurazepam, halazepam, lorazepam, medazepam, nitrazepam, oxazepam, prazepam, quazepam, temazepam and triazolam. The abuse of benzodiazepines has prompted a need to monitor the concentration in urine. Benzodiazepines are metabolized to a variety of derivatives and the majority of the metabolites are excreted in the urine as glucuronides, for example, see Clin. Pharm. Ther. 19, 443 (1976), Arz. Forsch. 22, 687 (1972) and Clin. Pharm. Ther. 20, 329 (1976).
The preparation of antibodies to benzodiazepine metabolites requires the synthesis of a benzodiazepine derivative in order to covalently attach the derivative to an antigenic polypeptide or protein. In addition, the benzodiazepine derivative is covalently attached to various polypeptides, proteins or labels for use in screening antibodies and in the immunoassay process. The benzodiazepine derivative should mimic the structure of the benzodiazepine metabolite sought to be measured. Therefore, the selection and synthesis of the types of benzodiazepine derivatives for covalent attachment to proteins, polypeptides or labels is critical. In addition, the benzodiazepine derivatives need to be stable and soluble in an aqueous solution.
Benzodiazepine compounds and conjugates for immunization and immunoassay have been described in U.S. Pat. Nos. 4,046,636, 4,083,948, 4,243,654 and 4,869,895.